Sterol Regulatory Element-binding Protein-1c Research Articles

Dimethyloxalylglycine Suppresses SREBP1c and Lipogenic Gene Expressions in Hepatocytes Independently of HIF1A.

Dimethyloxalylglycine (DMOG) is a representative inhibitor of the prolyl hydroxylase domain (PHD), which mediates the degradation of hypoxia-inducible factor-1-alpha (HIF1A). DMOG exerts its pharmacological effects via the canonical pathway that involves PHD inhibition; however, it remains unclear whether DMOG affects lipogenic gene expression in hepatocytes. We aimed to elucidate the effects of DMOG on sterol regulatory element-binding protein-1c (SREBP1c), a master regulator of fatty acid synthesis in hepatocytes. DMOG treatment inhibited SREBP1c mRNA and protein expression in HepG2 and AML12 hepatocytes and reduced the transcript levels of SREBP1c-regulated lipogenic genes. A luciferase reporter assay revealed that DMOG inhibited the transcriptional activity of SREBP1c. Moreover, DMOG suppressed SREBP1c expression in mice liver. Mechanistically, treatment with DMOG enhanced the expression of HIF1A and insulin-induced gene 2 (INSIG2), which inhibits the activation of SREBP1c. However, HIF1A or INSIG2 knockdown failed to reverse the inhibitory effect of DMOG on SREBP1c expression, suggesting a redundant role of HIF1A and INSIG2 in terms of repressing SREBP1c. DMOG did not function through the canonical pathway involving inhibition of SREBP1c by PHD, highlighting the presence of non-canonical pathways that mediate its anti-lipogenic effect.

Timosaponin A3 Induces Anti-Obesity and Anti-Diabetic Effects In Vitro and In Vivo.

Obesity is a serious global health challenge, closely associated with numerous chronic conditions including type 2 diabetes. Anemarrhena asphodeloides Bunge (AA) known as Jimo has been used to address conditions associated with pathogenic heat such as wasting-thirst in Korean Medicine. Timosaponin A3 (TA3), a natural compound extracted from AA, has demonstrated potential therapeutic effects in various disease models. However, its effects on diabetes and obesity remain largely unexplored. We investigated the anti-obesity and anti-diabetic properties of TA3 using in vitro and in vivo models. TA3 treatment in NCI-H716 cells stimulated the secretion of glucagon-like peptide 1 (GLP-1) through the activation of phosphorylation of protein kinase A catalytic subunit (PKAc) and 5'-AMP-activated protein kinase (AMPK). In 3T3-L1 adipocytes, TA3 effectively inhibited lipid accumulation by regulating adipogenesis and lipogenesis. In a high-fat diet (HFD)-induced mice model, TA3 administration significantly reduced body weight gain and food intake. Furthermore, TA3 improved glucose tolerance, lipid profiles, and mitigated hepatic steatosis in HFD-fed mice. Histological analysis revealed that TA3 reduced the size of white adipocytes and inhibited adipose tissue generation. Notably, TA3 downregulated the expression of lipogenic factor, including fatty-acid synthase (FAS) and sterol regulatory element-binding protein 1c (SREBP1c), emphasizing its potential as an anti-obesity agent. These findings revealed that TA3 may be efficiently used as a natural compound for tackling obesity, diabetes, and associated metabolic disorders, providing a novel approach for therapeutic intervention.

Cyy-287, a novel pyrimidine-2,4-diamine derivative, efficiently mitigates inflammatory responses, fibrosis, and lipid synthesis in obesity-induced cardiac and hepatic dysfunction.

Inflammation and metabolic disorders are important factors in the occurrence and development of obesity complications. In this study, we investigated the protective effect and underlying mechanism of a novel pyrimidine-2,4-diamine derivative, Cyy-287, on mice fed a high-fat diet (HFD). The mice were randomly separated into four groups (n ≥ 7): control (regular diet), HFD, HFD with Cyy-287 (5 mg/kg), and HFD with Cyy-287 (20 mg/kg) following HFD feeding for 10 weeks. After a 10-week administration, ALT and AST enzymes, echocardiography, immunohistochemical (IHC), Western blot (WB), Masson and Sirius Red staining were used to evaluate functional and morphological changes to the heart and liver. Microsomes from the mouse liver were extracted to quantify the total amount of CYP450 enzymes after drug treatment. Cyy-287 decreased the levels of serum glucose, LDL, TC, ALT, and AST activities in HFD-treated mice. However, Cyy-287 administration increased ejection fraction (EF) and fractional shortening (FS) index of the heart. Cyy-287 inhibited histopathological changes in the heart and liver; decreased inflammatory activity; significantly diminished p38 mitogen-activated protein kinase (MAPK), the nuclear factor-kappa B (NF-κB) axis, and sterol regulatory element-binding protein-1c (SREBP-1c); and upregulated the AMP-activated protein kinase (AMPK) pathway in HFD-treated mice. Cyy-287 restored the content of hepatic CYP450 enzymes. These findings demonstrated that Cyy-287 protected heart and liver cells from obesity-induced damage by inhibiting inflammation, fibrosis, and lipid synthesis.

Bacoside-A repressed the differentiation and lipid accumulation of 3T3-L1 preadipocytes by modulating the expression of adipogenic genes.

Obesity is one of the more complicated diseases, it can induce numerous life-threatening diseases mainly diabetes mellitus, cardiovascular disease, hypertension, and certain cancers. In this study, we assessed the efficacy of bacoside-A (a dammarane-type triterpenoid saponin derived from the plant Bacopa monniera Linn.) on the adipogenesis of 3T3-L1 preadipocytes. Results of this study illustrated that bacoside-A decreased the differentiation of 3T3-L1 cell, as evidenced by diminution of lipid droplets, which contains triglycerides and other lipids. During the differentiation process, transcription factors, which are mainly participating in adipogenesis such us CCAAT/enhancer-binding protein α (C/EBPα) and C/EBPβ, peroxisome proliferator-activated receptor-γ (PPARγ), and sterol regulatory element-binding protein-1c (SREBP-1c), expressions were significantly suppressed by bacoside-A. In addition, bacoside-A showed a potent reduction in genes precise to adipocytes such as lipoprotein lipase (LPL), fatty acid synthase (FAS), adipocyte fatty acid-binding protein (FABP4), and leptin expressions. Further, bacoside-A stimulated the phosphorylation of acetyl CoA carboxylase (ACC) and AMP-activated protein kinase (AMPK). These results demonstrated that bacoside-A has anti-adipogenic effects by regulating the transcription factors involved in adipocyte differentiation. Therefore, bacoside-A might be considered as a potent therapeutic agent for alleviating obesity and hyperlipidemia.

GPAT1 Activity and Abundant Palmitic Acid Impair Insulin Suppression of Hepatic Glucose Production in Primary Mouse Hepatocytes

BackgroundGlycerol-3-phosphate acyltransferase (GPAT) activity is correlated with obesity and insulin resistance in mice and humans. However, insulin resistance exists in people with normal body weight, and individuals with obesity may be metabolically healthy, implying the presence of complex pathophysiologic mechanisms underpinning insulin resistance. ObjectiveWe asked what conditions related to GPAT1 must be met concurrently for hepatic insulin resistance to occur. MethodsMouse hepatocytes were overexpressed with GPATs via adenoviral infection or exposed to high or low concentrations of glucose. Glucose production by the cells and phosphatidic acid (PA) content in the cells were assayed, GPAT activity was measured, relative messenger RNA expressions of sterol-regulatory element-binding protein 1c (SREBP1c), carbohydrate response element-binding protein (ChREBP), and GPAT1 were analyzed, and insulin signaling transduction was examined. ResultsOverexpressing GPAT1 in mouse hepatocytes impaired insulin’s suppression of glucose production, together with an increase in both N-ethylmaleimide-resistant GPAT activity and the content of di-16:0 PA. Akt-mediated insulin signaling was inhibited in hepatocytes that overexpressed GPAT1. When the cells were exposed to high-glucose concentrations, insulin suppression of glucose production was impaired, and adding palmitic acid exacerbated this impairment. High-glucose exposure increased the expression of SREBP1c, ChREBP, and GPAT1 by ∼2-, 5-, and 5.7-fold, respectively. The addition of 200 mM palmitic acid or linoleic acid to the culture media did not change the upregulation of expression of these genes by high glucose. High-glucose exposure increased di-16:0 PA content in the cells, and adding palmitic acid further increased di-16:0 PA content. The effect was specific to palmitic acid because linoleic acid did not show these effects. ConclusionThese data demonstrate that high-GPAT1 activity, whether induced by glucose exposure or acquired by transfection, and abundant palmitic acid can impair insulin’s ability to suppress hepatic glucose production in primary mouse hepatocytes.

Studies on the Effect of Piperine on Hepatocyte Nuclear Factor 1 Alpha (HNF-1α) and Sterol Regulatory Element-Binding Protein 1c (SREBP-1c) Levels in High-Fat-Diet and Sucrose-Induced Type 2 Diabetes Mellitus Rats.

Piperine, a naturally occurring compound in black pepper (Piper nigrum), is known for its potential health benefits, including its reported enhancement of insulin sensitivity. However, the precise impact of piperine on hepatocyte nuclear factor 1 alpha (HNF-1α) and sterol regulatory element-binding protein 1c (SREBP-1c), transcription factors for insulin signaling and glucose metabolism in hepatocytes, remains unclear. This study aims to investigate the effect of piperine, compared to metformin, on blood glucose and insulin levels by modifying the expression of hepatic HNF-1α and SREBP-1c in high-fat-diet (HFD) and sucrose-induced type 2 diabetes mellitus (T2DM) rats and in human Chang liver cells. Adult male albino rats were categorized into four groups: group 1 as the control, group 2 as T2DM, group 3 as T2DM rats treated with piperine (40 mg), and group 4 as T2DM rats treated with metformin (50 mg). Fasting blood glucose (FBG) and serum insulin levels were measured using enzyme-linked immunosorbent assay (ELISA), while real-time polymerase chain reaction (RT-PCR) analysis was conducted to assess the mRNA expression of HNF-1α and SREBP-1c. Further, piperine was treated with normal and high glucose-induced Chang liver cells, and gene expression was analysed.Data analysis was performed using one-way analysis of variance (ANOVA), with a significance set at p<0.05. Treatment with piperine led to a notable decrease in blood glucose levels and circulating insulin when compared with T2DM rats (group 2). Additionally, piperine administration resulted in the upregulation of HNF-1α mRNA expression and downregulation of SREBP-1c mRNA levels whose effects were found to be near that of the control and standard drug metformin's effects. In vitro study also confirmed that piperine improved the HNF-1αexpression and reduced the expression of SREBP-1c in Chang liver cells. Our findings suggest that piperine treatment effectively regulates hyperglycemic and hyperinsulinemic insulin resistance in the liver by modulating the expression of HNF-1α and SREBP-1c. Consequently, piperine emerges as a promising candidate for therapeutic intervention in managing T2DM.

Laminaria japonica Aresch-Derived Fucoidan Ameliorates Hyperlipidemia by Upregulating LXRs and Suppressing SREBPs.

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide, and hyperlipidemia is one major inducing factor of CVD. It is worthy to note that fucoidans are reported to have hypolipidemic activity with species specificity; however, the underlying mechanisms of action are far from clarification. This study is aimed at investigating the plasma lipid-lowering mechanisms of the fucoidan from L. japonica Aresch by detecting the levels of hepatic genes that are involved in lipid metabolism. Our results demonstrated that the fucoidan F3 significantly lowered total cholesterol and triglyceride in C57BL/6J mice fed a high-fat diet. In the mouse liver, fucoidan F3 intervention significantly increased the gene expression of peroxisome proliferator-activated receptor (PPAR) α, liver X receptor (LXR) α and β, and ATP-binding cassette transporter (ABC) G1 and G8 and decreased the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), low-density lipoprotein receptor, cholesterol 7 alpha-hydroxylase A1, and sterol regulatory element-binding protein (SREBP) 1c and SREBP-2. These results demonstrated that the antihyperlipidemic effects of fucoidan F3 are related to its activation of PPARα and LXR/ABC signaling pathways and inactivation of SREBPs. In conclusion, fucoidan F3 may be explored as a potential compound for prevention or treatment of lipid disorders.

Microbe-derived Antioxidants Enhance Lipid Synthesis by Regulating the Hepatic AMPKα–SREBP1c Pathway in Weanling Piglets

BackgroundWeaning usually causes low feed intake and weight loss in piglets, which mobilizes lipid to energize. The microbe-derived antioxidants (MAs) exhibit great potential in antioxidation, anti-inflammation, and metabolic regulation. ObjectivesWe aimed to investigate the changes of lipid metabolism postweaning and effects of MA on growth performance and hepatic lipid metabolism in weanling piglets. MethodsIn the first experiment, piglets weaned at 21 d of age were slaughtered on weaning day (d0), 4 (d4), and 14 (d14) postweaning (6 piglets per day). In the second experiment, piglets were divided into 2 groups, receiving MA (MA) and saline gavage (CON), respectively. All piglets were weaned at 21 d of age and 6 piglets from each group were slaughtered at 25 d of age. ResultsIn experiment 1, the serum triglyceride, total cholesterol (TC), and LDL cholesterol on d4 and d14 declined significantly compared with d0 (P < 0.05). The serum leptin on d0 was higher than that on d4 and d14 (P < 0.05). The serum ghrelin kept increasing from d0 to d14 (P < 0.05). The hepatic hormone-sensitive lipase and adipose triglyceride lipase first increased from d0 to d4 and then decreased from d4 to d14 (P < 0.05). In experiment 2, the average daily gain and average daily feed intake from 21 to 25 d of age increased in the MA group compared with the CON group (P < 0.05). The serum TC, hepatic TC, and glucose of MA group showed a significant increase than that of the CON group (P < 0.05). The expression of SCD1, ACAT2, and PPARγ were upregulated in the MA group (P < 0.05). Contrary to the decreased expression of phosphorylation of adenosine 5′-monophosphate-activated protein kinase alfa subunit (Thr172), the nuclear sterol regulatory element–binding protein 1c, fatty acid synthase, and peroxisome proliferator-activated receptor gamma of MA group increased than that of CON group (P < 0.05). ConclusionsWeaning promoted hepatic lipolysis and MA could enhance lipid synthesis by regulating adenosine 5′-monophosphate-activated protein kinase alfa subunit–sterol regulatory element–binding protein 1c pathway, thus improving growth performance of weanling piglets.

Glycyrrhizic acid restores the downregulated hepatic ACE2 signaling in the attenuation of mouse steatohepatitis

Glycyrrhizic acid (GA), one of the major active components derived from licorice root, exerts liver-protecting activity. Its molecular mechanisms of action, however, remain not completely understood. The angiotensin (Ang) converting enzyme (ACE) 2/Ang-(1–7)/Mas axis, regulated by ACE2 through converting Ang II into Ang-(1–7) to activate Mas receptor, counteracts the pro-inflammatory and pro-steatotic effects of the ACE/Ang II/Ang II receptor type 1 (AT1) axis. Here, it was found that pretreatment with GA suppressed LPS/D-galactosamine-induced serum hyperactivities of alanine aminotransferase and aspartate aminotransferase, hepatomegaly, pathological changes, and over-accumulation of triglycerides and fatty droplets in the liver of mice. GA also diminished LPS/free fatty acid-induced inflammation and steatosis in cultured hepatocytes. Mechanistically, GA restored hepatic protein hypoexpression of ACE2 and Mas receptor, and the decrease in hepatic Ang-(1–7) content. Hepatic overexpression of angiotensin II and AT1 was also suppressed. However, GA did not alter hepatic protein expression of renin and ACE. In addition, GA inhibited hepatic protein over-phosphorylation of the p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, extracellular signal-regulated kinase, and nuclear factor κB at Ser536. Hepatic overexpression of tumor necrosis factor α, interleukin 6, interleukin 1β, sterol regulatory element-binding protein 1c, and fatty acid synthase was also inhibited. GA-elicited recovery of ACE2 and Mas protein hypoexpression was further confirmed in the hepatocyte. Thus, the present results demonstrate that GA restores the downregulated hepatic ACE2-mediated anti-inflammatory and anti-steatotic signaling in the amelioration of steatohepatitis. We suggest that GA may protect the liver from injury by regulating the hepatic ACE2-mediated signaling.

Gypenoside XIII regulates lipid metabolism in HepG2 hepatocytes and ameliorates nonalcoholic steatohepatitis in mice.

Gypenoside XIII is isolated from Gynostemma pentaphyllum (Thunb.) Makino. In mice, G. pentaphyllum extract and gypenoside LXXV have been shown to improve non-alcoholic steatohepatitis (NASH). This study investigated whether gypenoside XIII can regulate lipid accumulation in fatty liver cells or attenuate NASH in mice. We used HepG2 hepatocytes to establish a fatty liver cell model using 0.5 mM oleic acid. Fatty liver cells were treated with different concentrations of gypenoside XIII to evaluate the molecular mechanisms of lipid metabolism. In addition, a methionine/choline-deficient diet induced NASH in C57BL/6 mice, which were given 10 mg/kg gypenoside XIII by intraperitoneal injection. In fatty liver cells, gypenoside XIII effectively suppressed lipid accumulation and lipid peroxidation. Furthermore, gypenoside XIII significantly increased SIRT1 and AMPK phosphorylation to decrease acetyl-CoA carboxylase phosphorylation, reducing fatty acid synthesis activity. Gypenoside XIII also decreased lipogenesis by suppressing sterol regulatory element-binding protein 1c and fatty acid synthase production. Gypenoside XIII also increased lipolysis and fatty acid β-oxidation by promoting adipose triglyceride lipase and carnitine palmitoyltransferase 1, respectively. In an animal model of NASH, gypenoside XIII effectively decreased the lipid vacuole size and number and reduced liver fibrosis and inflammation. These findings suggest that gypenoside XIII can regulate lipid metabolism in fatty liver cells and improve liver fibrosis in NASH mice. Therefore, gypenoside XIII has potential as a novel agent for the treatment of NASH.

Cornelian Cherry (Cornus mas L.) Fruit Extract Lowers SREBP-1c and C/EBPα in Liver and Alters Various PPAR-α, PPAR-γ, LXR-α Target Genes in Cholesterol-Rich Diet Rabbit Model.

Cornelian cherry (Cornus mas L.) fruits, abundant in iridoids and anthocyanins, are natural products with proven beneficial impacts on the functions of the cardiovascular system and the liver. This study aims to assess and compare whether and to what extent two different doses of resin-purified cornelian cherry extract (10 mg/kg b.w. or 50 mg/kg b.w.) applied in a cholesterol-rich diet rabbit model affect the levels of sterol regulatory element-binding protein 1c (SREBP-1c) and CCAAT/enhancer binding protein α (C/EBPα), and various liver X receptor-α (LXR-α), peroxisome proliferator-activated receptor-α (PPAR-α), and peroxisome proliferator-activated receptor-γ (PPAR-γ) target genes. Moreover, the aim is to evaluate the resistive index (RI) of common carotid arteries (CCAs) and aortas, and histopathological changes in CCAs. For this purpose, the levels of SREBP-1c, C/EBPα, ATP-binding cassette transporter A1 (ABCA1), ATP-binding cassette transporter G1 (ABCG1), fatty acid synthase (FAS), endothelial lipase (LIPG), carnitine palmitoyltransferase 1A (CPT1A), and adiponectin receptor 2 (AdipoR2) in liver tissue were measured. Also, the levels of lipoprotein lipase (LPL), visceral adipose tissue-derived serine protease inhibitor (Vaspin), and retinol-binding protein 4 (RBP4) in visceral adipose tissue were measured. The RI of CCAs and aortas, and histopathological changes in CCAs, were indicated. The oral administration of the cornelian cherry extract decreased the SREBP-1c and C/EBPα in both doses. The dose of 10 mg/kg b.w. increased ABCA1 and decreased FAS, CPT1A, and RBP4, and the dose of 50 mg/kg b.w. enhanced ABCG1 and AdipoR2. Mitigations in atheromatous changes in rabbits' CCAs were also observed. The obtained outcomes were compared to the results of our previous works. The beneficial results confirm that cornelian cherry fruit extract may constitute a potentially effective product in the prevention and treatment of obesity-related disorders.

Ethyl acetate fraction of oregano seed protects non-alcoholic fatty liver in high-fat diet-induced obese mice through modulation of Srebp-1c.

Oregano (Origanum vulgare) seed is used as spices and is known to have anti-inflammatory, antibacterial, and antioxidant effects. The anti-fatty liver effects of oregano seed ethyl acetate (OSEA) were evaluated in high-fat diet (HFD)-induced obese mice. OSEA was orally administered with HFD for 10 weeks. The body weight, aspartate aminotransferase, alanine aminotransferase, cholesterol, triglyceride, and low-density lipoprotein levels in the HFD with 100 mg/kg of OSEA significantly decreased by approximately 1.21-, 1.44-, 2.12-, 1.12-, 1.05, and 1.59 times, respectively, while high-density lipoprotein levels increased by approximately 1.05 times compared to those in the HFD group (p < .05). In addition, the distribution of liver fat in the HFD with 100 mg/kg OSEA (OSEA 100) group decreased significantly (p < .05). Therefore, OSEA supplementation can ameliorate fatty liver disease and reduce the accumulation of triglycerides in adipose tissue. The expression of genes involved in liver fat accumulation, such as sterol regulatory element-binding protein-1c (Srebp-1c), fatty acid synthase (Fas), stearoyl-CoA desaturase-1 (Scd1), and acetyl-CoA carboxylase 1 (Acc1), significantly decreased in OSEA 100 by approximately 2.6-, 1.74-, 1.89-, and 1.56-times, respectively (p < .05). Therefore, OSEA may modify obesity and liver fat accumulation by regulating the expression of genes involved in lipid metabolism.

Conjugated Linoleic Acid Reduces Lipid Accumulation via Down-regulation Expression of Lipogenic Genes and Up-regulation of Apoptotic Genes in Grass Carp (Ctenopharyngodon idella) Adipocyte In Vitro.

The relationship between conjugated linoleic acid (CLA) and lipogenesis has been extensively studied in mammals and some cell lines, but it is relatively rare in fish, and the potential mechanism of action of CLA reducing fat mass remains unclear. The established primary culture model for studying lipogenesis in grass carp (Ctenopharyngodon idella) preadipocytes was used in the present study, and the objective was to explore the effects of CLA on intracellular lipid and TG content, fatty acid composition, and mRNA levels of adipogenesis transcription factors, lipase, and apoptosis genes in grass carp adipocytes in vitro. The results showed that CLA reduced the size of adipocyte and lipid droplet and decreased the content of intracellular lipid and TG, which was accompanied by a significant down-regulation of mRNA abundance in transcriptional regulators including peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer-binding protein (C/EBP) α, sterol regulatory element-binding protein (SREBP) 1c, lipase genes including fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), lipoprotein lipase (LPL). Meanwhile, it decreased the content of saturated fatty acids (SFAs) and n - 6 polyunsaturated fatty acid (n-6 PUFA) and increased the content of monounsaturated fatty acid (MUFA) and n - 3 polyunsaturated fatty acid (n-3 PUFA) in primary grass carp adipocyte. In addition, CLA induced adipocyte apoptosis through downregulated anti-apoptotic gene B-cell CLL/lymphoma 2 (Bcl-2) mRNA level and up-regulated pro-apoptotic genes tumor necrosis factor-α (TNF-α), Bcl-2-associated X protein (Bax), Caspase-3, and Caspase-9 mRNA level in a dose-dependent manner. These findings suggest that CLA can act on grass carp adipocytes through various pathways, including decreasing adipocyte size, altering fatty acid composition, inhibiting adipocyte differentiation, promoting adipocyte apoptosis, and ultimately decreasing lipid accumulation.

DWN12088, A Prolyl-tRNA Synthetase Inhibitor, Alleviates Hepatic Injury in Nonalcoholic Steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a liver disease caused by obesity that leads to hepatic lipoapoptosis, resulting in fibrosis and cirrhosis. However, the mechanism underlying NASH is largely unknown, and there is currently no effective therapeutic agent against it. DWN12088, an agent used for treating idiopathic pulmonary fibrosis, is a selective prolyl-tRNA synthetase (PRS) inhibitor that suppresses the synthesis of collagen. However, the mechanism underlying the hepatoprotective effect of DWN12088 is not clear. Therefore, we investigated the role of DWN12088 in NASH progression. Mice were fed a chow diet or methionine-choline deficient (MCD)-diet, which was administered with DWN12088 or saline by oral gavage for 6 weeks. The effects of DWN12088 on NASH were evaluated by pathophysiological examinations, such as real-time quantitative reverse transcription polymerase chain reaction, immunoblotting, biochemical analysis, and immunohistochemistry. Molecular and cellular mechanisms of hepatic injury were assessed by in vitro cell culture. DWN12088 attenuated palmitic acid (PA)-induced lipid accumulation and lipoapoptosis by downregulating the Rho-kinase (ROCK)/AMP-activated protein kinase (AMPK)/sterol regulatory element-binding protein-1c (SREBP-1c) and protein kinase R-like endoplasmic reticulum kinase (PERK)/α subunit of eukaryotic initiation factor 2 (eIF2α)/activating transcription factor 4 (ATF4)/C/EBP-homologous protein (CHOP) signaling cascades. PA increased but DWN12088 inhibited the phosphorylation of nuclear factor-κB (NF-κB) p65 (Ser536, Ser276) and the expression of proinflammatory genes. Moreover, the DWN12088 inhibited transforming growth factor β (TGFβ)-induced pro-fibrotic gene expression by suppressing TGFβ receptor 1 (TGFβR1)/Smad2/3 and TGFβR1/glutamyl-prolyl-tRNA synthetase (EPRS)/signal transducer and activator of transcription 6 (STAT6) axis signaling. In the case of MCD-diet-induced NASH, DWN12088 reduced hepatic steatosis, inflammation, and lipoapoptosis and prevented the progression of fibrosis. Our findings provide new insights about DWN12088, namely that it plays an important role in the overall improvement of NASH. Hence, DWN12088 shows great potential to be developed as a new integrated therapeutic agent for NASH.

DNAJA1 positively regulates amino acid-stimulated milk protein and fat synthesis in bovine mammary epithelial cells.

Several cellular processes, including the recovery of misfolded proteins, the folding of polypeptide chains, transit of polypeptides across the membrane, construction and disassembly of protein complexes, and modulation of protein control, are carried out by DnaJ homologsubfamily A member 1(DNAJA1), which belongs to the DnaJ heat-shock protein family. It is unknown if DNAJA1 regulates the production of milk in bovine mammary epithelium cells (BMECs). Methionine and leucine increased DNAJA1 expression and nuclear location, as seen by us. In contrast to DNAJA1 knockdown, overexpression of DNAJA1 boosted the production of milk proteins and fats as well as mammalian target of rapamycin (mTOR) and sterol regulatory element binding protein-1c(SREBP-1c). As a result of amino acids, mTOR and SREBP-1c gene expression are stimulated, and DNAJA1 is a positive regulator of BMECs'amino acid-induced controlled milk protein and fat production.

Positive effects of rutin on egg quality, lipid peroxidation and metabolism in post-peak laying hens.

Excessive fat deposition due to impaired fat metabolism in chickens is a major problem in the poultry industry. Nutritional interventions are effective solutions, but current options are limited. A safe phytochemical, rutin, has shown positive effects in animals, but its effect on lipid metabolism in poultry remains unknown. Hence, this study is to investigate the effects of rutin on egg quality, serum biochemistry, fat deposition, lipid peroxidation and hepatic lipid metabolism in post-peak laying hens. A total of 360 Taihang laying hens (49-week-old) were randomly divided into five groups and fed a basal diet (control group, 0%) and a basal diet supplemented with 300 (0.03%), 600 (0.06%), 900 (0.09%), and 1,200 (0.12%) mg rutin/kg feed, respectively. The results showed that eggshell strength was significantly (p < 0.05) higher in the dietary rutin groups, whereas yolk percentage (p < 0.05), total cholesterol (TC) (p < 0.01) and yolk fat ratio (p < 0.01) decreased linearly (p < 0.05) in the dietary rutin groups. Importantly, dietary rutin reduced serum triglyceride (TG) and TC levels, decreased abdominal lipid deposition and liver index (p < 0.05), and which concomitantly decreased hepatic lipid (TG, TC, and free fatty acid) accumulation (p < 0.05). An increase (p < 0.05) in total antioxidant capacity and superoxide dismutase activity and a decrease (p < 0.05) in malondialdehyde levels were also found. At the same time, the activities of hepatic lipase, acetyl-CoA carboxylase and malic enzyme in the liver were decreased (p < 0.05). Dietary rutin also increased (p < 0.05) the expression of fatty acid oxidation-related genes (carnitine palmitoyl transferase 1, peroxisome proliferator-activated receptor α, farnesoid X receptor). Additionally, it decreased fatty acid synthesis genes (sterol regulatory element binding protein-1c, acetyl-CoA carboxylase α, stearoyl-CoA desaturase 1) (p < 0.05). In conclusion, the addition of rutin (0.06-0.12%) to the diet improved the fat metabolism and increased liver antioxidant capacity in post-peak laying hens, and these positive changes improved egg quality to some extent.

A novel bellidifolin intervention mitigates nonalcoholic fatty liver disease-like changes induced by bisphenol F.

As a potential endocrine-disrupting chemical, bisphenol F (BPF) may cause nonalcoholic fatty liver disease (NAFLD)-like changes, but the mechanisms underpinning its pathogenesis as well as the intervention strategies remain poorly understood. Using the electron microscopy technology, along with LipidTOX Deep Red neutral and Bodipy 493/503 staining assays, we observed that BPF treatment elicited a striking accumulation of lipid droplets in HepG2 cells, accompanied by an increased total level of triglycerides. At the molecular level, the lipogenesis-associated mRNAs and proteins, including acetyl-CoA carboxylase, fatty acid synthase, stearoyl-CoA desaturase-1, peroxisome proliferator-activated receptor gamma, and CCAAT-enhancer-binding proteins, increased significantly via the AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) signaling regulation in both in vitro and in vivo studies. Furthermore, the immunofluorescence results also showed the robust lipogenesis induced by BPF, evident in its ability to promote the translocation of sterol regulatory element-binding protein-1c from the cytoplasm to the nuclei. To investigate the intervention strategies for BPF-induced NAFLD-like changes, we demonstrated that bellidifolin, isolated and purified from Swertia chirayita, significantly attenuated BPF-induced lipid droplet deposition in HepG2 cell and NAFLD-like changes in mice by blocking the expression of lipogenesis-associated proteins. Therefore, the present study elucidates the mechanisms underlying BPF-induced lipid accumulation in HepG2 cells, while also highlighting the potential of bellidifolin to mitigate BPF-induced NAFLD-like changes.

Molecular Approach to Identify Anti-inflammatory Potential of Stevioside in HFD-induced Type 2 Diabetic Rats: Evidence From in Vivo Study

Stevioside is a natural sweetener derived from the leaves of the Stevia rebaudiana plant. It has gained popularity as a sugar substitute due to its intense sweetness without adding calories or affecting blood sugar levels, making it a suitable option for people with diabetes or those looking to reduce their sugar intake. Studies have shown that stevioside has glucose lowering effects. Previous studies have shown that it has significant role in skeletal muscle but its role on expression of inflammatory signaling molecules in adipose tissue against high diet and sucrose-induced type-2 diabetes in experimental rats is yet to be done. The current research was undertaken to investigate if stevioside could also exert its antidiabetic effects by circumventing adipocyte induced inflammation, a key driving factor for insulin resistance in obese individuals. Effective dose of stevioside (20 mg/kg b.wt) was administered orally for 45 days to high fat diet and sucrose induced type-2 diabetic rats. Interestingly, stevioside treatment restores the elevated serum levels of proinflammatory cytokines including tumor necrosis factor-α (TNF-α) and sterol regulatory element binding protein-1c (SREBP-1c) and enhances Peroxisome Proliferator–activated receptor-γ (PPAR-γ) in adipocytes of diabetic rats. The gene expression of IR, GLUT4 and PPAR-γ mRNA were also significantly activated in stevioside treated groups but reduced IL-1 beta, IlL-6, IKKB, TNF-alpha and NFkB mRNA expression in diabetic adipose tissue. More importantly, stevioside acts very effectively as metformin to circumvent inflammation and insulin resistance in diabetic rats. Our results clearly show that stevioside inhibits obesity induced insulin resistance by ameliorating the inflammatory events and upregulating insulin signalling molecules. Keywords: Stevioside, HFD-T2DM, pro inflammation, insulin signalling; adipose tissue, obesity; signaling pathways; Therapautics.

Antioxidant and Anti-Obesity Effects of Juglans mandshurica in 3T3-L1 Cells and High-Fat Diet Obese Rats.

Juglans mandshurica Maxim. walnut (JMW) is well-known for the treatment of dermatosis, cancer, gastritis, diarrhea, and leukorrhea in Korea. However, the molecular mechanism underlying its anti-obesity activity remains unknown. In the current study, we aimed to determine whether JMW can influence adipogenesis in 3T3-L1 preadipocytes and high-fat diet rats and determine the antioxidant activity. The 20% ethanol extract of JMW (JMWE) had a total polyphenol content of 133.33 ± 2.60 mg GAE/g. Considering the antioxidant capacity, the ABTS and DPPH values of 200 μg/ml of JMWE were 95.69 ± 0.94 and 79.38 ± 1.55%, respectively. To assess the anti-obesity activity of JMWE, we analyzed the cell viability, fat accumulation, and adipogenesis-related factors, including CCAAT-enhancer-binding protein alpha (C/EBPα), sterol regulatory element-binding protein-1c (SREBP1c), peroxisome proliferator-activated receptor-gamma (PPARγ), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC). We found that total lipid accumulation and triglyceride levels were reduced, and the fat accumulation rate decreased in a dose-dependent manner. Furthermore, JMWE suppressed adipogenesis-related factors C/EBPα, PPARγ, and SREBP1c, as well as FAS and ACC, both related to lipogenesis. Moreover, animal experiments revealed that JMWE could be employed to prevent and treat obesity-related diseases. Hence, JMWE could be developed as a healthy functional food and further explored as an anti-obesity drug.

Prenatal exposure to low-dose di-(2-ethylhexyl) phthalate (DEHP) induces potentially hepatic lipid accumulation and fibrotic changes in rat offspring

Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer that is widely used to enhance the flexibility and durability of various products. As an endocrine disruptor, DEHP can interfere with normal hormonal functions, posing substantial health risks to organisms. Given the critical role of the liver in DEHP metabolism, we investigated potential liver damage in offspring induced by prenatal exposure to low doses of DEHP in Sprague Dawley rats. Pregnant rats were divided into three groups and administered 20 or 200 μg/kg/day of DEHP or corn oil vehicle control via oral gavage from gestation days 0–20. Male rat offspring were euthanized on postnatal day 84, and blood and liver specimens were collected for analysis. We observed fibrotic changes in the livers of the exposed groups, accompanied by the proliferation and activation of hepatic stellate cells and upregulated expression of TGF-B and collagen 1A1. Additionally, an inflammatory response, characterized by increased macrophage infiltration and elevated levels of pro-inflammatory cytokines, was evident. Third, hepatic and serum triglyceride and serum cholesterol were notably increased, along with upregulated expression of lipid metabolism-related proteins, such as sterol regulatory element-binding protein-1c, acetyl-CoA carboxylase, fatty acid synthase, and diacylglycerol O-acyltransferase 1, particularly in the low-dose group. These results suggest that prenatal exposure to DEHP can disrupt lipid metabolism, resulting in hepatic lipid accumulation in the offspring. This exposure may also induce an inflammatory response that contributes to the development of liver fibrosis. Thus, even at relatively low doses, such exposure can precipitate latent liver damage in offspring.